GPs nmea connection to vhf dcs

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alapicz

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Hi
After spending 2 hours trying to understand how to connect my vhf dcs to chartplotter I gave up ,so now I'm looking for some help how and advice

My vhf Is standard horizon eclipse GX 1300E and manual says to connect:
Yellow nmea gps input(+) connect to nmea out(+)
Green nmea gps input ( -) connect to nmea out (-)
White nmea dsc output (+) connect to nmea in(+)
Brown nmea dsc output (+) connect to nmea in(-)

My gps is garmin gpsmap 550 and have nmea description:
Red-power
Black- ground (power and nmea0183)
Blue- NMEA 0183 port 1 tx out
Brown- NMEA 0183 port rx in
Grey-NMEA 0183 port 2 tx out
Violet-NMEA 0183 port 2rx in
Green -CANet L
White -CANet H
Orange- accessory on
Yellow -alarm low
I really couldn't work which colours connect together so if someone have any experience I'll really appreciate

Also can I connect this gps to ais nasa engine?
Thanks
 
prv said:
GPS black to VHF green (and also to power negative).
GPS blue to VHF yellow.

Pete
Click to expand...

Pete's right. What you are looking at is connecting a Garmin "single wire" system to a "two wire system"... It's also better practice to ensure that your plotter and radio are on the same power circuit, or at least directly connected via the -ve
 
Thanks , will this connection work if ((hopefully never)I press dcs button? I mean do my vhf will send signal to gps and than my position will be known?
 
alapicz said:
Thanks , will this connection work if ((hopefully never)I press dcs button? I mean do my vhf will send signal to gps and than my position will be known?
Click to expand...
Your vhf should give an alarm if it is not receiving a position from your gps. If it's not you may have it disabled in the settings or it may be yours doesn't do that someone with that particular vhf might be able to advise you or it should have it in the instructions.
Your vhf does not send a signal to the gps. When you press the red button it already has a position from the gps and it sends out DSC alarm.
 
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alapicz said:
Thanks , will this connection work if ((hopefully never)I press dcs button? I mean do my vhf will send signal to gps and than my position will be known?
Click to expand...

Once the connection is established the GPS will be constantly sending position to the VHF. If you press the DSC button it will transmit the position with the DSC alert- the position will at most be a couple of seconds old, that's all.

The VHF does not in some way 'request' a position from the GPS when you make a distress call.

Just beaten to the explanation by Spyro :)
 
prv said:
GPS black to VHF green (and also to power negative).
GPS blue to VHF yellow.

Pete
Click to expand...

Pete's description is good, but I think you can improve on it. I'm pretty sure the GX1300 has two way NMEA. So it will take your GPS position (it should show on screen if it is receiving a position by displaying the Long Lat at the bottom of the screen), but it should also be able to send a DSC Position Request or DSC Alert with Position to your GPS. That is handy when someone hits their red button and you want to know are they near by and you can assist or are they 30NM away and it will take you 10 hours to get there, but they are in UK Coastal Waters so someone else will be nearer or a rescue asset.

To do that connect:
Code: 
SH GX1300e       to    GPSMap500
===========================
Yellow           to    Blue
Green            to    Black*
Brown            to    Black
White            to    Brown

*Black also connected to battery negative

Also can I connect this gps to ais nasa engine?
Click to expand...
There is a second output so should be possible. Not sure you need to send any data from the plotter to the AIS, but can't see any harm doing so. Are you already getting AIS data in to the plotter - if so do nothing. If not its worth connecting...

To do that connect:
Code: 
GPSMap500                 to      NASA-AIS
=====================================
Battery Negative          to      Black Stripe
Grey                      to      Blue
Violet                    to      Black
Black                     to      Silver

However, the baud rate on Port 2 needs increased to 38400 and I think that will be too fast for the Grey-Blue which should be on 4800. Substituting Blue and Red on the NASA may work. But actually I don't think you need either Blue or Red connected to grey. I don't think there is any advantage...
 
And if the wires are connected correctly its a device issue -

- baud rate wrong on talk / listener?
- not listening at all?
- sentence type not what is expected?
 
Not listening at all , manual says that after connection I should have my position display on VHF unfortunately there nothing. I have check settings on plotter all looks correct
 
From the VHF manual:

If everything is OK, you should get small satellite symbol appear in the top right of the VHF display. If the connection is there but there's a problem, the symbol will flash.

What do you get: permanent symbol, flashing symbol or no symbol?

You will need to make sure that the GPS POrt 1 output is set to 4800 Baud, NMEA0183 sentences. According to the Garmin manual, you can set Port 1 as follows:

1. From the Home screen, select Configure > Communications > NMEA 0183 Setup.
2. Select a setting (Sounder, Route, System, or Garmin).
3. Select the NMEA 0183 output sentence to toggle the output on or off.

In 1, it doesn't say what these options do but I'd guess Route or System will give info the radio can understand.
 
FulmarJeddo said:
I seem to recall, by default the Garmin GPSMAP 550 has the ports disabled. You will need to go into the Communication menu to enable port 1 and set it to nmea and 4800 baud.
Click to expand...

Yip -

Home / Configuration / Communications/ Serial Port 1/ NMEA Standard 0183 Setup:
Set to: Route or Maybe System (not Garmin or Sonar)
You are ideally looking for an RMC sentence but I'm not sure the Garmin tells you what its sending,..

You should also go to:
Home / Configure / Other Vessels:
DSC - On
 
May I suggest that first you check that you have an NMEA output from your GPS, you can Identify the correct cables pretty simply with a LED, DigitalYacht did a great explanation here... http://digitalyacht.co.uk/files/Tech%2000019-2011.pdf

Once you've identified the correct cables on the GPS try connecting the GPS you have a couple of options, you can either connect it up to the VHF and see if you get a position, if not try changing the Baud rate in the VHF, if that doesn't work I would suggest connecting the GPS to a PC, you'll need a laptop, usb to serial adapter and a serial cable. Wire the ground (-ve) to pin 5 on the cable and signal (+ve) to pin3 (on a female plug), connect it all up then use a program like DigitalYacht NMEA data display program.

This will display the raw serial data, just select the correct port. If the text is all garbled try changing the baud rate till you see "real" text.

Now check the baud rate on your VHF and change as required, if you get this far and are still having issues drop me a message.
 
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syneraida said:
May I suggest that first you check that you have an NMEA output from your GPS, you can Identify the correct cables pretty simply with a LED, DigitalYacht did a great explanation here... http://digitalyacht.co.uk/files/Tech%2000019-2011.pdf

Once you've identified the correct cables on the GPS try connecting the GPS you have a couple of options, you can either connect it up to the VHF and see if you get a position, if not try changing the Baud rate in the VHF, if that doesn't work I would suggest connecting the GPS to a PC, you'll need a laptop, usb to serial adapter and a serial cable. Wire the ground (-ve) to pin 5 on the cable and signal (+ve) to pin3 (on a female plug), connect it all up then use a program like DigitalYacht NMEA data display program.

This will display the ray serial data, just select the correct port. If the text is all garbled try changing the baud rate till you see "real" text.

Now check the baud rate on your VHF and change as required, if you get this far and are still having issues drop me a message.
Click to expand...

You've twice mentioned changing the baud rate on the VHF. So as not to confuse the OP, it's worth noting that there's no way of changing the baud rate on a GX1300E, it just needs input at 4800baud.
 
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